This application is based on and claims priority under 35 U.S.C. xc2xa7119 with respect to a Japanese Patent Application 2001-350725, filed on Nov. 15, 2001, the entire content of which is incorporated herein by reference.
This invention generally relates to a door apparatus for a vehicle. More particularly, this invention pertains to a vehicle door apparatus capable of moving a door in an opening direction by use of a moving unit assembled between a vehicle body and the door and a driving unit for detecting a moving speed of the door and for controlling the detected moving speed thereof.
Conventionally, a vehicle body is equipped with a sensor for detecting an entirely open position of a door such as a slide door. When the slide door is opened in an opening direction for uncovering a door opening portion by use of a driving motor, a slidably moving operation of the slide door is terminated at the entirely open position based upon the detection of the sensor. That is, this type of known slide door apparatus for a vehicle includes, for example an on/off switch equipped to the vehicle body. When a pushing member equipped to the slide door operates the on/off switch, the slide door is judged to have been moved to the entirely open position. The rotational speed of the driving motor is then decelerated so as to terminate the slidably moving operation of the slide door in the opening direction.
When the slide door is slidably moved in the opening direction for uncovering the door opening portion, the moving speed of the vehicle door is first accelerated up to a predetermined speed by the driving motor. The slide door is slidably moved in the opening direction at the predetermined speed until the on/off switch is pressed. The slide door can be moved in the opening direction with a predetermined stroke along a slide rail fixed to the vehicle body. An edge portion at an opening side of the stroke is defined by a stopper which can come in contact with the slide door. The on/off switch is located at a position where the on/off switch is pressed by the slide door before the slide door is slidably moved to the edge portion at the opening side of the stroke. Therefore, the slide door can effectively come in contact with the stopper under the condition that the moving speed of the slide door in the opening direction has been already decelerated to a certain speed level.
However, according to the known vehicle slide door apparatus having the on/off switch, the slide door may come in contact with the stopper with an unexpectedly large force before the moving speed of the slide door is sufficiently decelerated at a desired position. The unexpected contact with the slide door and the stopper may occur due to an error for attaching the switch to the vehicle body, a malfunction of the switch, a displacement of the long-used switch, or some other factors. To overcome the aforementioned problem, the stopper and the position for attaching the on/off switch are required to be strengthened. Further, as far as the switch is required to be equipped for recognizing the entirely open position of the slide body, it takes some troubles with equipping the switch. Therefore, the known vehicle slide door apparatus include some points to be improved such as the operational performance, the manufacturing cost, and the like.
From another aspect, there are some types of vehicles each of which is provided with an intermediate stopper fixed to the slide door for preventing a window member assembled to the slide door from being left open when the slide door is slidably moved in the opening direction. For example, the intermediate stopper projects from the vehicle door towards the vehicle body when a window glass is opened with a predetermined opening amount. The intermediate stopper of the slide door can come in contact with a portion of the vehicle body before the slide door is slidably moved to the entirely open position. Therefore, the driver can effectively be reminded of the window being left open.
However, the intermediate stopper takes various postures relative to the slide door so that the intermediate stopper cannot be always provided with a sufficient strength. According to the known slide door apparatus, the slide door is slidaly moved in the opening direction at the predetermined speed until the slide door is slidably moved to a portion adjacent to the entirely open position. When the intermediate stopper is provided for the known slide door apparatus, the intermediate stopper may come in contact with the vehicle body with an unexpectedly large force. In this case, the intermediate stopper needs to have a sufficiently large strength to endure the unexpected contact with the vehicle body. Accordingly, it may require troubles for manufacturing the slide door apparatus with the intermediate stopper and a relatively high manufacturing cost thereof.
The present invention therefore seeks to provide an improved door apparatus for a vehicle capable of overcoming inconveniences of the known door apparatus and capable of completing the movement of the door in the opening direction without applying an impact force to the door or the vehicle body.
According to an aspect of the present invention, a door apparatus for a vehicle includes a door movable in an opening direction for uncovering an opening portion defined in a vehicle body and in a closing direction for covering the opening portion, a moving means assembled between the vehicle body and the door, a driving means for driving the door to be moved, and the driving means further detecting a moving speed of the door and controlling the detected moving speed of the door. The moving means includes a predetermined moving stroke in the opening direction and a decelerating area defined within the predetermined stroke for decelerating the moving speed of the door.
The door is moved in the opening direction at a first speed by use of the moving means and the driving means until the door reaches the decelerating area. The moving speed of the door in the opening direction is decelerated by the driving means from the first speed to a second speed being lower than the first speed while the door has been moved in the decelerating area. The movement of the door is stopped by the driving means when the door is moved beyond the decelerating area, the door comes in contact with an obstacle, and the moving speed of the door in the opening direction detected by the diving means becomes lower than a predetermined speed corresponding to an open position of the door by a predetermined threshold value.
The obstacle includes at least either an entirely opening stopper for specifying the open position of the door or an intermediate stopper for preventing a window member from being left open when the door is moved in the opening direction. The entirely opening stopper is provided for the vehicle body and comes in contact with the door when the door is positioned at an entirely open position. The entirely opening position corresponds to a position for uncovering the opening portion defined in the vehicle body. The intermediate stopper is provided for the vehicle body and takes various postures relative to the door in response to an opening amount of the window member and comes in contact with the door when the door is moved in the opening direction with the window member being left open with a predetermined opening amount. The door further comes in contact with the obstacle being entrapped between the door and the vehicle body and the movement of the door is stopped when the moving speed of the door becomes lower than the predetermined speed by the predetermined threshold value.
According to another aspect of the present invention, a movement of a door is stopped by a driving means when the door is moved beyond a decelerating area, a vehicle body comes in contact with an obstacle, and a moving speed of the door in an opening direction detected by the diving means becomes lower than a predetermined speed corresponding to an open position of the door by a predetermined threshold value.
The door is provided with at least either an entirely opening stopper or an intermediate stopper as the obstacle. The entirely opening stopper specifies the open position of the door and the intermediate stopper prevents a window member from being left open when the door is moved in the opening direction. The entirely opening stopper comes in contact with the vehicle body when the door is positioned at an entirely open position. The entirely opening position corresponds to a position for uncovering an opening portion defined in the vehicle body. The intermediate stopper takes various postures relative to the vehicle body in response to an opening amount of the window member and comes in contact with the vehicle body when the door is moved in the opening direction with the window member being left open with a predetermined opening amount.